The invention relates in general to aircraft canopy jettison apparatus and in particular to aircraft canopy jettison apparatus that include an airbag.
There are three known ways to jettison an aircraft canopy during an emergency egress situation. The three ways are rocket motors, canopy thruster(s), and canopy fragilization. All three have advantages and disadvantages that dictate the effectiveness of a pilot's safe egress from an aircraft.
Many older military aircraft still in service use a canopy thruster in combination with mechanical linkages to remove the canopy from an aircraft. Some of the limitations of using a canopy thruster have been seen over the past few years. Timing is a key factor to ensuring the successful egress of aircrew from an aircraft. The use of mechanical linkages to assist in the removal has a strong dependence on the resilience of these linkages. The failure of one part in the series of linkages can cause the canopy to remain attached to the aircraft or cause a delay in the timing of events and possible injury to the aircrew.
Canopy jettison by way of rocket motors is currently used in military aircraft. One problem with using rocket motors is the extreme amounts of noise generated, which can damage an aircrew's hearing. Another problem with using rocket motors is the proximity of the rocket plume to the aircrew, which can cause serious injury to the aircrew.
Canopy fragilization has recently been incorporated into new aircraft designs over the past decade as a means for canopy removal during an emergency egress situation. One disadvantage of canopy fragilization is the use of explosives, in close proximity to the aircrew, to blow the transparent glass out of the canopy's metal frame. One concern when using this method is the likelihood of fragments hitting the aircrew. Another disadvantage is the noise that may be encountered due to the proximity of the aircrew to the explosive charge. One key factor to a successful disintegration of the transparent glass is in the determination of how much explosive material is needed to fragment the transparent part of the canopy into small pieces.